Field of the Invention
The invention relates to a device used for conducting mechanical property tests on fragile materials, in particular to a device fixing rock samples in direct cyclic tension and compression tests for a testing machine.
Description of the Related Art
Due to structural limits of a sample fixing device, only a unidirectional compression test or a unidirectional tension measurement can be conducted in a rock test.
The unidirectional tension test still has the following shortcomings: (1) test results are not accurate; (2) it is easy to damage rock samples and not conducive to the test of the mechanical effect after rock test peak stress; and (3) it is not easy to operate and the labor intensity is relatively high.
In a unidirectional compression test, samples can only bear compression load but can't bear direct tension load. Therefore, a cyclic alternate compression and tension load test can't be conducted.